rs121918616

Variant names:

• chr1-160130283-G-A
• rs121918616
• NM_000702.4:c.1643G>A

Variant summary

Our verdict is Pathogenic. The variant received 17 ACMG points: 17P and 0B. PM2 PM5 PP2 PP3_Strong PP5_Very_Strong

The NM_000702.4(ATP1A2):​c.1643G>A​(p.Arg548His) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000205 in 1,461,882 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Pathogenic (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R548C) has been classified as Pathogenic.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000021 (0 hom.)
• Consequence: ATP1A2 NM_000702.4 missense
• Clinical Significance: Pathogenic criteria provided, multiple submitters, no conflicts P:6
• Conservation: PhyloP100: 9.75
• Publications: 9 publications found

Genes affected

ATP1A2 (HGNC:800): (ATPase Na+/K+ transporting subunit alpha 2) The protein encoded by this gene belongs to the family of P-type cation transport ATPases, and to the subfamily of Na+/K+ -ATPases. Na+/K+ -ATPase is an integral membrane protein responsible for establishing and maintaining the electrochemical gradients of Na and K ions across the plasma membrane. These gradients are essential for osmoregulation, for sodium-coupled transport of a variety of organic and inorganic molecules, and for electrical excitability of nerve and muscle. This enzyme is composed of two subunits, a large catalytic subunit (alpha) and a smaller glycoprotein subunit (beta). The catalytic subunit of Na+/K+ -ATPase is encoded by multiple genes. This gene encodes an alpha 2 subunit. Mutations in this gene result in familial basilar or hemiplegic migraines, and in a rare syndrome known as alternating hemiplegia of childhood. [provided by RefSeq, Oct 2008]

ATP1A2 Gene-Disease associations (from GenCC):

• hemiplegic migraine-developmental and epileptic encephalopathy spectrum

  Inheritance: AD Classification: DEFINITIVE Submitted by: ClinGen
• migraine, familial hemiplegic, 2

  Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: G2P, Ambry Genetics, Genomics England PanelApp, Labcorp Genetics (formerly Invitae)
• alternating hemiplegia of childhood 1

  Inheritance: AD Classification: STRONG, LIMITED Submitted by: Ambry Genetics, Labcorp Genetics (formerly Invitae), Genomics England PanelApp
• developmental and epileptic encephalopathy 98

  Inheritance: AD Classification: STRONG, MODERATE Submitted by: Ambry Genetics, G2P, Labcorp Genetics (formerly Invitae)
• fetal akinesia, respiratory insufficiency, microcephaly, polymicrogyria, and dysmorphic facies

  Inheritance: AR Classification: STRONG, MODERATE Submitted by: G2P, Ambry Genetics, Labcorp Genetics (formerly Invitae)
• alternating hemiplegia of childhood

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• familial or sporadic hemiplegic migraine

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Pathogenic. The variant received 17 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr1-160130282-C-T is described in ClinVar as Pathogenic. ClinVar VariationId is 871961.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
• PP2: Missense variant in the ATP1A2 gene, where missense mutations are typically associated with disease (based on misZ statistic). The gene has 63 curated pathogenic missense variants (we use a threshold of 10). The gene has 10 curated benign missense variants. Gene score misZ: 4.7713 (above the threshold of 3.09). Trascript score misZ: 6.824 (above the threshold of 3.09). GenCC associations: The gene is linked to developmental and epileptic encephalopathy 98, fetal akinesia, respiratory insufficiency, microcephaly, polymicrogyria, and dysmorphic facies, migraine, familial hemiplegic, 2, alternating hemiplegia of childhood, alternating hemiplegia of childhood 1, familial or sporadic hemiplegic migraine, hemiplegic migraine-developmental and epileptic encephalopathy spectrum.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.99
• PP5: Variant 1-160130283-G-A is Pathogenic according to our data. Variant chr1-160130283-G-A is described in ClinVar as Pathogenic. ClinVar VariationId is 12926.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_000702.4. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	ATP1A2	NM_000702.4	MANE Select	c.1643G>A	p.Arg548His	missense	Exon 12 of 23	NP_000693.1

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	ATP1A2	ENST00000361216.8	TSL:1 MANE Select	c.1643G>A	p.Arg548His	missense	Exon 12 of 23	ENSP00000354490.3
	ATP1A2	ENST00000392233.7	TSL:5	c.1643G>A	p.Arg548His	missense	Exon 12 of 23	ENSP00000376066.3
	ATP1A2	ENST00000447527.1	TSL:2	c.773G>A	p.Arg258His	missense	Exon 5 of 16	ENSP00000411705.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD2 exomes AF: 0.00000398 AC: 1 AN: 251212 AF XY: 0.00

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00000881

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000205 AC: 3 AN: 1461882 Hom.: 0 Cov.: 32 AF XY: 0.00000138 AC XY: 1 AN XY: 727244

African (AFR) AF: 0.00 AC: 0 AN: 33480

American (AMR) AF: 0.00 AC: 0 AN: 44724

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26136

East Asian (EAS) AF: 0.00 AC: 0 AN: 39700

South Asian (SAS) AF: 0.00 AC: 0 AN: 86258

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53410

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5768

European-Non Finnish (NFE) AF: 0.00000270 AC: 3 AN: 1112010

Other (OTH) AF: 0.00 AC: 0 AN: 60396

GnomAD4 genome Cov.: 32

Alfa AF: 0.00 Hom.: 0

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:6

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Migraine, familial basilar Pathogenic:1

Dec 13, 2005

OMIM

Significance: Pathogenic

Review Status: no assertion criteria provided

Collection Method: literature only

Developmental and epileptic encephalopathy 98 Pathogenic:1

Apr 26, 2024

Institute of Human Genetics, Heidelberg University

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

not provided Pathogenic:1

Sep 23, 2025

GeneDx

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Published in vitro functional studies demonstrated that R548H variant results in reduced ATPase activity, alters the affinity for sodium and potassium, and reduces catalytic turnover compared to the wild type protein (PMID: 23954377); Not observed at significant frequency in large population cohorts (gnomAD); In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; This variant is associated with the following publications: (PMID: 18498390, 16088919, 27445835, Maksemous2019article, 16344534, 23954377, 18184292)

Migraine, familial hemiplegic, 2 Pathogenic:1

Jul 18, 2024

Institute of Human Genetics, University of Leipzig Medical Center

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Criteria applied: PS4_MOD,PM2,PM5,PS3_SUP,PP1,PP2,PP3

ATP1A2-related disorder Pathogenic:1

Rady Children's Institute for Genomic Medicine, Rady Children's Hospital San Diego

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant has been previously reported as a heterozygous change in patients with Hemiplegic migraine and Basilar migraine (PMID: 16344534, and Maksemous et al., 2019). Additionally, a different variant at the same amino acid position (p.Arg548Cys) has been seen in multiple patients with ATP1A2-Related Disorders (ClinVar Variation ID: 871961). In vitro overexpression studies revealed that the c.1643G>A (p.Arg548His) variant has reduced Na(+) affinity and increased K(+) affinity, leading to reduced catalytic turnover compared to the wild type protein (PMID: 23954377). It is present in the heterozygous state in the gnomAD population database at a frequency of 0.0004% (1/251212) and thus is presumed to be rare. The c.1643G>A (p.Arg548His) variant affects a highly conserved amino acid and is predicted by multiple in silico tools to have a deleterious effect on protein function. Based on the available evidence, the c.1643G>A (p.Arg548His) variant is classified as Pathogenic.

Familial hemiplegic migraine Pathogenic:1

Mar 12, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces arginine, which is basic and polar, with histidine, which is basic and polar, at codon 548 of the ATP1A2 protein (p.Arg548His). This variant is present in population databases (rs121918616, gnomAD 0.0009%). This missense change has been observed in individuals with clinical features of autosomal dominant ATP1A2-related conditions (PMID: 16344534; Invitae; Maksemous et al. 2019 Cephalagia Reports Vol. 2). ClinVar contains an entry for this variant (Variation ID: 12926). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is expected to disrupt ATP1A2 protein function with a positive predictive value of 80%. Experimental studies have shown that this missense change affects ATP1A2 function (PMID: 23954377). This variant disrupts the p.Arg548 amino acid residue in ATP1A2. Other variant(s) that disrupt this residue have been observed in individuals with ATP1A2-related conditions (PMID: 18498390), which suggests that this may be a clinically significant amino acid residue. For these reasons, this variant has been classified as Pathogenic.

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	1.0
BayesDel_addAF	Pathogenic	0.53	D
BayesDel_noAF	Pathogenic	0.52
CADD	Pathogenic	32
DANN	Pathogenic	1.0
DEOGEN2	Pathogenic	0.91	D
Eigen	Uncertain	0.68
Eigen_PC	Uncertain	0.65
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Uncertain	0.94	D
M_CAP	Pathogenic	0.32	D
MetaRNN	Pathogenic	0.99	D
MetaSVM	Uncertain	0.53	D
MutationAssessor	Pathogenic	4.2	H
PhyloP100		9.7
PrimateAI	Pathogenic	0.83	D
PROVEAN	Uncertain	-4.1	D
REVEL	Pathogenic	0.94
Sift	Pathogenic	0.0	D
Sift4G	Pathogenic	0.0	D
Polyphen		1.0	D
Vest4		0.98
MutPred		0.97		Gain of catalytic residue at L550 (P = 0.0544)
MVP		0.98
MPC		2.0
ClinPred		1.0	D
GERP RS		4.6
Varity_R		0.68
gMVP		0.90
Mutation Taster		=7/93	disease causing (ClinVar)

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.0		Details are displayed if max score is > 0.2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Other links and lift over

dbSNP: rs121918616; hg19: chr1-160100073;